Arc-electrode.



110. 789,609. PATENTED MAY 9, 1905. D. ALHOLMES, S. A. TUCKER & B. VANWAGENEN.

ARC ELECTRODE. APPLICATION FILED AUG. 6, 1904.

Canbzklb and/ ,Biniliw' u mum 70m Juneau. 51716221268 WIT/(885 ,JzmueZyvfucfiez' Z, Eda/M42761: Yiyenem UNITED STATES Patented May 9, 1905.

PATENT OEEIcE.

DUNCAN A. HOLMES, SAMUEL A. TUCKER, AND ED\VARD VAN IVAGENEN, OF NEIVYORK, N. Y.

ARC-ELECTRODE.

SPECIFICATION forming part of Letters Patent No. 789,609, dated May 9,1905.

Application filed August 6, 1904!: Serial No. 219,793.

To all whom, it Duty concern:

Be it known that we, DUNCAN A. HoLMEs, SAMUEL A. TUCKER, and EDWARD VANAG- ENEN, citizens of the United States, and resi dents of the city ofNew York, borough of Manhattan, in the county and State of New York,have invented a new and Improved Arc- Electrode, of which the followingis a full, clear, and exact description.

Our invention relates to electrodes used more particularly forare-lighting; and it consists of a composition of matter from which thearc-electrodes are formed.

The shape of the arc-electrode forms no part of the invention. Ifdesired, therefore, it may have the ordinary form, such as is shown inthe accompanying drawing, forming a part of this specification.

The composition used for the purpose of forming the electrode containszirconium carbid, mixed with any desired percentage of a bindingmaterial, such as coal-tar, lam p-black, molasses, &c.

The zirconium carbid is usually manufactured in an electric furnace andis prepared from the mineral zircon admixed with an excess of carbon. Asthe preparation is made at a very high temperature, the silicon from thezircon is distilled off, leaving the zirconium and carbon to form thedesired carbid. The method of manufacturing the compound mentioned.however, has but little to do with our invention and is mentioned inconnection with the fact that the compound thus formed having been madeat a comparatively high temperature is of great stability and is noteasily broken up or even volatilized by the application of heat exceptat exceedingly high temperatures.

l/Ve find that electrodes made of the compound above mentioned give alight of unusual intensi'ty, and the light appears to proceed fromtheflame of the are--that is, from the portion intermediate of theelectrodetips-rather than from the crater of the positive electrode andthe peak of the negative electrode.

The are from our electrode may be drawn out to a relatively greaterlength, depending upon the voltage and current employed, and it; isextinguished with a notable snap or report when the current is broken.

Our theory as to the increased efliciency is that the refractorysubstance used is neither decomposed nor volatilized by heating exceptat high temperatures, and as a consequence the material particles thrownoff into the flame of the arc and before being decomposed are raised toa high degree of incandescence. The exact action going on in the are,however, is unknown, and we wish it to be understood that our claim isnot to be limited by any fallacy in the alleged cause of the actiondescribed. Vhatever may be the ultimate nature of the action ofarc-lights in general, and of ours in particular, the fact remains thatthe substance mentioned produces a light of exceptional brilliance whencompared with arclights of other kinds which are subjected to the sameconditions of temperature,(or voltage and current.)

lVe have also discovered that if infusible substances are added to thecomposition of the electrodes the small material particles in the areare raised to a higher degree of incandescence than usual, and hence thechiciency of the light is increased, and this applies particularly toour electrode herein described, as the composition is so chosen that themaximum luminosity is thus obtained.

Having thus described our invention, we claim as new and desire tosecure by Letters Patent-- An arc-electrode consisting of zirconiumcarbid (ZrC) admixed with a suitable binding material.

In testimony whereof we have signed our names to this specification inthe presence of the subscribing witnesses.

DUNCAN A. HOLMES. SAMUEL A. TUCKER. El) WA RD VAN \VAGENEN.

lVitnesscs as to signature of Duncan A. Holmes:

DANIEL l V. BEDEoED, "ILLIAM. M. NAUGHTON.

\Vitncsses as to signature of Samuel A. Tucker:

J. F. S'rETsoN, T. J. Fnuncu.

Subscribingwitnesses to the signature of Edward Van \Vagenen:

WM. ll. Runs, JOHN P. B'nznnan.

